Could cannabis replace opioids ? – content of the article
President Trump officially declared the opioid crisis a “public health emergency” in October 2017. At the time, the number of opioid overdose deaths in the United States was approaching 50,000, and nearly 60% of them were caused by illicit synthetic opioids such as fentanyl or tramadol. The problem has continued to escalate. Last year, there were more than 80 000 deaths from opioid overdoses, of which around 90% were caused by strong synthetic forms. This crisis is not getting better and new strategies are needed to tackle it.
Does cannabis legalisation reduce opioid use?
There are several reasons why legalizing marijuana appears to be a promising strategy to combat the ongoing opioid crisis. First, according to early population-based reports, opioid overdose deaths have declined in states that have legalized medical marijuana. However, these findings are no longer valid when the time of analysis is extended to the present; any benefit of marijuana legalization on reducing opioid overdoses appears to be short-lived.
States that legalized recreational cannabis experienced an initial 7.6% reduction in opioid-related emergency room visits compared with states that did not legalize cannabis, but this difference disappeared within 6 months. It remains possible that marijuana can serve as a substitute for common prescription opioids such as oxycodone, codeine or hydrocodone, but cannot overcome the severity of dependence on more potent illicit opioids such as fentanyl or heroin, which are increasingly abused.
Some studies show a significant reduction in prescription opioid use in patients who also use cannabis, but this benefit disappears in tightly controlled clinical trials. These clinical trials have not found consistent results for concurrent use of cannabis and prescription opioids, although most patients report a preference for marijuana over opioids.
How can cannabis replace opioids?
There are currently 15 clinical trials investigating the ability of cannabis to reduce the need for opioids. These clinical trials are driven by evidence from animal studies that are difficult to ignore, looking at the pain-relieving interactions between the endocannabinoid system, which is stimulated by cannabinoids such as THC, and the opioid system.
Pain experiments on rodents have consistently shown that THC reduces the need for opioids. In seven different studies, THC reduced the effective dose of morphine by 3.5 times. Three key pieces of evidence support this beneficial effect:
- Many cannabinoids, such as THC, stimulate CB1 receptors in the endocannabinoid system, which are located in the same brain regions involved in pain processing as opioid receptors and may also contribute to pain reduction.
- CB1 receptors in the body interact with opioid receptors to increase their analgesic effects in rodent studies.
- CB2 receptors, another cannabinoid target, can stimulate the release of the body’s own opioids, which activate pain-relieving opioid receptors.
So why is there a discrepancy between these ongoing clinical trials and the population studies mentioned above?
The direct reason is unclear. Some argue that the sense of control over pain management that one experiences when one chooses to use cannabis may promote better outcomes. This effect could explain why patients who may have chosen to use marijuana together in some studies reduced their need for opioids, as opposed to randomized clinical trials.
It is also possible that these benefits are due to the placebo effect, where people can increase their opioid levels without medication and control their pain simply because they think they are receiving an active painkiller.
Furthermore, the results are misleading because the opioid-reducing effects of cannabis may disappear with long-term use of high-THC products, which are increasingly common in legal markets. Studies on the opioid-reducing effects of THC in rodents are often short-lived, usually lasting only a few days, whereas marijuana use in humans is often chronic – people take it for weeks or longer. Repeated use of high-potency THC leads to tolerance, which is often due to reduced levels of CB1 receptors and generally weaker endocannabinoid signalling.
Thus, the development of tolerance to THC would hinder the ability of CB1 and opioid receptors to work together to control pain. This could explain why short-term rodent studies show opioid-reducing benefits from THC and how these effects are often lost in long-term clinical trials in humans.
Furthermore, this phenomenon could explain the initial decrease in opioid overdoses when states legalise marijuana, but as tolerance develops over several months, the opioid-reducing effects of cannabis disappear in the population.
Given all the current evidence, there is no clear consensus on whether cannabis can replace or reduce the need for opioids in pain management.
Could cannabis replace opioids – Video
Are there risks associated with the simultaneous use of cannabis and opioids?
In some cases, combining cannabis with opioids has been associated with poorer mental health, and this combination may be worse for people over 65. Yet other safety issues, such as opioid respiratory depression, have not worsened with concurrent marijuana use, which at least alleviates some concerns.
And in most cases, concomitant cannabis use does not increase opioid use, disproving the idea that marijuana is a gateway drug, a warning many drug warriors have sounded.
Can CBD help opioid addiction?
Despite the lack of clinical evidence that hemp can replace opioids, CBD is emerging as a potential strategy to help people trying to overcome opioid use disorder.
Italy inadvertently legalised CBD-rich hemp in 2017 (essentially ‘hemp’ by US legal standards) and has seen a reduction in opioid use, suggesting that CBD-rich hemp could replace opioids in the short term.
Several clinical studies have shown that CBD reduces the signals that trigger opioid cravings and suppresses the heightened stress response that accompanies cravings. Results from rodent studies show that CBD reduces many of the negative changes in behaviour, anxiety and genetic expression that accompany opioid withdrawal and lead to relapse.
These studies have set the stage for additional clinical trials (such as the one to be held at the Tarzana Treatment Center in Los Angeles) to explore the potential of CBD as an adjunctive therapy for opioid use disorder.
Published by Blood30/03/2023